Intraoperative M-Entropy Measurements

Completed

• Conditions: General Anesthesia
• Interventions: Device: study cases

• Registration Number: NCT00599066
• Lead Sponsor: University of Oklahoma

Brief Summary

The purpose of this study is to learn more about an Entropy monitor that the anesthesiologist will be using.

Detailed Description

Depth of anesthesia monitors are increasingly used in clinical anesthesia practice. Bispectral Index (BIS) and M-Entropy are examples to these devices, both of which are available at our institution. Both BIS and M-Entropy use a unilateral, single channel of EEG to derive a number indicating the anesthetic depth. These devices have similar disposable skin probes that can be applied on either side of the forehead. Since the depth of anesthesia for an individual is the same over the whole brain cortex at a given point in time, BIS numbers obtained over the left and right side of the forehead should agree. The same should be true for M-Entropy as well.

A recent study, however, showed that two separate BIS probes, applied over the left and right forehead of the same patient at the same time, can give significantly different numbers. This has not been studied for M-Entropy. BIS and M-Entropy use different mathematical algorithms that process the raw EEG signal to compute a numeric value. Therefore, it is possible that M-Entropy may show different results in a similar study setup.

The aim is to investigate the same-patient reproducibility of M-Entropy by monitoring and recording Entropy variables over both the left and the right side of the forehead of patients under general anesthesia.

Study Timeline

• Study Start: 2007-09
• Study First Submitted: 2007-12-20
• Study First Submitted QC: 2008-01-22
• Study First Posted: 2008-01-23
• Primary Completion: 2008-06
• Study Completion: 2009-04
• Status Verified: 2017-04
• Last Update Submitted: 2017-04-12
• Last Update Posted: 2017-04-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 24

Inclusion Criteria

• Patients scheduled to have surgery under general anesthesia, with a minimum of 60 minutes expected duration.

Exclusion Criteria

• Non-English speaker
• Patients younger than 18 years of age

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Study cases	study cases	Application of a second M-Entropy probe on the forehead of the patient; at the end the patient will have 2 probes on the forehead, one in the right and one in the left.

Primary Outcome Measures

Name	Time	Method
The investigators hypothesize that simultaneous M-Entropy measurements from the left and right side of the forehead of a person do not differ during general anesthesia.	1 year

Trial Locations

Locations (1)

OU MEDICAL CENTER, Presbyterian Tower, OR; 🇺🇸 Oklahoma City, Oklahoma, United States